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%I #13 Jan 31 2017 16:18:59
%S 0,0,0,1,2,3,4,7,8,9,10,14,14,17,18,23,24,27,26,32,32,35,36,44,42,47,
%T 48,52,50,58,54,65,62,67,66,78,70,79,78,88,84,94,88,100,100,103,100,
%U 118,106,119,114,124,116,135,122,138,134,141,136,155,142,155,154,163,156
%N a(n) = Sum_{i+j=n} omega(i)*omega(j), where omega = A001221.
%H Ivan Neretin, <a href="/A112965/b112965.txt">Table of n, a(n) for n = 1..10000</a>
%F G.f.: (Sum_{k>=1} x^prime(k)/(1 - x^prime(k)))^2. - _Ilya Gutkovskiy_, Jan 31 2017
%t Table[Sum[PrimeNu[i]*PrimeNu[n - i], {i, n - 1}], {n, 65}] (* _Ivan Neretin_, Jan 21 2017 *)
%o (PARI) a(n) = sum(i=2, n-2, omega(i)*omega(n-i)); \\ _Michel Marcus_, Jan 22 2017
%Y Cf. A013939, A112966, A112967.
%K nonn
%O 1,5
%A _Reinhard Zumkeller_, Oct 07 2005
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